Abstract
OBJECTIVE: To evaluate intraocular pressure (IOP) and ocular perfusion pressure (OPP) changes during pediatric laparoscopic appendectomy performed in the Trendelenburg position and to identify potential perioperative ocular risks. METHODS: In this prospective observational study, IOP and OPP were measured in 25 ASA I pediatric patients undergoing emergency laparoscopic appendectomy. OPP was calculated as the difference between mean arterial blood pressure (MABP = diastolic BP + 1/3 [systolic BP – diastolic BP]) and IOP. Measurements were obtained with a Tono-Pen Avia(®) tonometer at eight standardized intraoperative timepoints (T1–T8), including the pneumoperitoneum and Trendelenburg phases. Statistical analysis was performed using repeated-measures ANOVA with Bonferroni post hoc correction. RESULTS: A significant rise in IOP was observed during Trendelenburg positioning, with peak values at T6 (approximately the 10th minute in Trendelenburg). Paired-samples comparisons demonstrated significantly higher left-eye IOP during Trendelenburg (T5–T6), with mean interocular differences of 1.32 mmHg (T5, p < 0.001) and 1.32 mmHg (T6, p = 0.00001). A mixed-effects model (fixed factors: time × eye; random intercept for subject) confirmed a strong time effect (p < 0.001) and a trend-level interaction (p ≈ 0.08), supporting side-dependent IOP elevation. OPP showed a transient decline during pneumoperitoneum and Trendelenburg, with a minimum mean of 48.5 ± 4.0 mmHg at T6 (p < 0.01). Transient IOP elevations above 21 mmHg occurred in 5 of 25 patients (20%), all resolving within minutes after desufflation. No postoperative ocular complications were observed. CONCLUSION: Trendelenburg positioning during pediatric laparoscopy causes transient but statistically significant alterations in IOP and OPP. Although these changes were short-lived and clinically asymptomatic in healthy children, perioperative ocular risk assessment remains important in patients with glaucoma, elevated baseline IOP, or optic nerve vulnerability.